Teething tube



FIG. 1 is a top, front, left perspective view of a teething tube, showing my new design;

FIG. 2 is a bottom, rear, right perspective view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof; and,

FIG. 5 is a front elevation view thereof, wherein the rear, left, and right views thereof are identical to the front elevation view.

The broken lines in the drawings depict portions of the teething tube that form no part of the claimed design. 

CLAIM I claim the ornamental design for a teething tube, as shown and described. 